Expander for ductile metal pipes and tubes



Oct. 24, 1950 A. CHAMPION 2,526,932

EXPANDER FOR DUCTILE METAL PIPES AND TUBES Filed July '7', 1948 ALFRED CHRMPION Au: 0 1' n w Patented Oct. 24, 1950 OFFICE EXPANDER FOR DUCTILE METAL PIPES AND TUBES Alfred Champion, Abbots Langley, England Application July 7, 1948, Serial No. 37,350 In Great Britain November 18, 1947 1 Claim.

This invention relates to devices for outwardly beading or deforming metal pipes and tubes of the'kind which comprise a perforated tubular mandrel wherein one or more movable beading elements is or are arranged together With an adjustable core by means of which the beading element or elements is or are supported and partly extruded through the perforated mandrel so as to efiect the required heading of the pipe or tube as the mandrel is rotated therein, the core being thereafter adjusted to disengage the beading element or elements so that the same is or are returned into the mandrel as the latter is removed from the beaded pipe or tube.

The object of the present invention is to simplify and improve the construction and design of expanding and beading devices of the kind referred to so as to facilitate the quick and accurate adjustment of the expanding and beading element or elements thereof and render the same more compact, robust and long wearing and Very efiicient, reliable and quick in operation.

In expanding and beading devices of the kind referred to, as heretofore proposed, the extrusion and return of the beading and expanding elements housed in the tubular mandrel are controlled by screw and similar longitudinal adjustments of the core relatively to the tubular mandrel, which adjustments are relatively slow and involve considerable loss of time.

According to the present invention the tubular mandrel and its adjustable core in an expanding and heading device of the kind referred to are made and assembled so that limited relative angular adjustments thereof can be immediately effected without longitudinal adjustments so as to control by means of a cam comprised in the adjustable core, the extrusion and return of the expanding and beading element or elements of the device, as each expanding or beading operation thereof is commenced and finished.

In a convenient construction the tubular mandrel is provided with an extension at one end, which is of smaller external diameter than the body of the mandrel, through which latter, together with its extension of reduced diameter, is formed a through longitudinal bore in which the adjustable core in the form of a spindle provided with a laterally disposed cam, can be rotatably mounted, such spindle being of sufiicient length to project beyond the mandrel body remote from its reduced extension, while the body of the mandrel is transversely slotted to intersect the longitudinal bore thereof so that the spindle-like core adjustably assembled in such bore is exposed in such slot.

The core is furnished with a screw socket arranged so as to register with the transverse slot in the body of the mandrel, and a screw stud or other stop is secured in such socket after the spindle-like core has been assembled in the bore of the mandrel and its externally reduced extension, which is provided on one side with a lateral perforation that intersects the bore of the extension, while the end of the spindle-like core housed in the bore of the extension is longitudinally cut away on one side and shaped to form a cam surface, the crest of which terminates adjacent to one longitudinal edge of the uncut circumference of the cylindrical segment of the spindle-like core, while the other end of the cam crest terminates either in a recessed curve or an inclined surface which intersects the opposite longitudinal edge of the uncut circumference of the spindle-like core.

With this construction the spindle-like core can be angularly adjusted within the limits of the circumferential slot formed in the body of the tubular mandrel.

When the core is turned so that its screw stud bears against the following end of the transverse slot in the mandrel, the .cam surface of the spindle-like core allows a beading element such as a steel ball to fall back in the lateral perforation in the externally reduced extension of the tubular mandrel.

The invention is further described with reference to the accompanying drawings wherein similar references indicate corresponding parts.

Figs. 1 and 2 are respectively external side and end views of one construction of tube expander or beader according to the present invention. Fig. 3 is a cross sectional view on the line III-III of Fig. 1, and Fig. 4 is a longitudinal sectional view showing the core of the expander adjusted so as to extend the beading element through the perforation in the reduced extension of the mandrel, and Fig. 5 a similar view showing the mandrel adjusted so that the steel ball forming the beading element is returned into the body of the mandrel. Fig. 6 is a cross section on the line VIVI, Fig. 1, further illustrating the form and adjustment of the core in the mandrel so as to extend the beading element through the perforated end of the bore, and Fig. '7 is a cross section on the line V1IVII of Fig. 5, further illustrating the adjustment of the core to enable the beading element to be returned into the mandrel body.

Referring to the drawing, I indicates th body of the tubular mandrel which is provided with a reduced extension 2, the external diameter of which is less than that of the body portion so as to form a shoulder 3 at the junction of such extension with the body of the mandrel.

4 indicates the longitudinal bore which extends eccentrically through the mandrel I and its extension, a section of such bore being enlarged within the mandrel I as shown in Figs. 4 and 5 so as to form an internal shoulder 5 between the enlarged section of the bore and its continuation through the reduced extension 2 of the mandrel.

The mandrel I has a transverse circumferential slot 6 formed therein which intersects the enlarged bore of the mandrel body I as shown in Figs. 3 and 4, while the reduced extension 2 is provided with a lateral perforation I which terminates in the bore of the reduced extension 2 of the mandrel.

8 indicates the adjustable core which is provided at one end with an externally reduced extension 9 adapted to make a sliding fit in, the reduced bore of such extension, while the core 8 is adapted to make a sliding fit in the enlarged bore of the tubular mandrel body I.

The shoulder II] at the junction of the core 8 with its reduced extension 9 abuts the internal shoulder 5 between the enlarged bore of the mandrel body and the bore of its reduced extension as shown in Figs. 4 and 5.

The reduced extension 9 of the core is longitudinally cut away on one side as indicated in Figs. 5, 6 and 7 and shaped so as to form a cam surfac comprising a crest I2 and a trough I2a, the crest I2 being formed generally by a portion of the circumference of the cylindrical segment of the spindle-like core, the trough being formed by the cut away portion of the core as shown in Figs. 6 and 7.

The core 8 is assembled in the body of the tubular mandrel so that its reduced extension 3 extends into the reduced bore of the reduced section 2 of the tubular mandrel and serves to support a steel ball or other similar beading element la in the lateral hole or perforation. I in the bore of the reduced extension 2 of the mandrel when the ball Ia is in its inoperative position as indicated in Figs. 5 and 7 of the drawings.

The core 8 is provided with a hole Id formed therein so as to register with the transverse slot in the tubular mandrel body I when the core is assembled therein, a screw threaded tubular stud I5 being secured therein so that it projects into the transverse slot 6 of the mandrel body I so as to prevent any appreciable longitudinal movement of the core 8 relatively to the mandrel I and the adjustable core 8 mounted therein.

The cor 8 is of suiiicient length to project beyond the end of the mandrel body I remote from its reduced extension 2 as shown in the drawings and in the construction illustrated has a transverse bore formed therein in which is mounted a sliding lever or handle I6. for operating the beading device.

The exterior of the reduced extension 2 of the tubular mandrel is adapted to make a sliding fit in a pipe or tube of corresponding internal diameter so that the external shoulder 3 between the body of the tubular mandrel and its reduced extension forms a stop against which the end of the pipe or tube to be beaded abuts, which determines the distance between the shoulder 3 of the mandrel and the perforation 7 in its reduced extension.

The pipe or tube indicated at A in Figs. 1 and 5 is suitably held in a tube vice or otherwis and the projecting end of the spindle-like adjustable core of the mandrel is then turned by means of its lever handle I6 until the stop pin on such core abuts the opposite end of the transverse slot of the mandrel, such angular adjustment of the core 8 relatively to the mandrel causing the lateral longitudinal cam on the reduced extension 9 of the core to lift and extend the steel ball Ia forming the beading element, through the lateral perforation 1 in the reduced extension 2 of the tubular mandrel and holds the ball in such extruded position while the whole device, including the tubular mandrel and its adjustable core, is rotated in the end of the relatively stationary pipe or tube in which the required bead is formed by a single turn or revolution of the tube expanding device.

On the completion of the beading operation, the spindle-like core is returned to its original position so that the return adjustment of the cam-like surface thereon allows the steel ball to drop back into th perforation in the reduced extension of the mandrel as the latter is withdrawn from the end of the beaded pipe or tube.

The improved swaging device may be made in various sizes and weights, according to the diameter and gauge of the pipes and tubes to be beaded or deformed.

I claim:

A device for beading tubes comprising, a cylindrical mandrel having a reduced extension, said mandrel having an eccentric bore, said extension having an eccentric bore forming an axial continuation of the bore in said mandrel and of smaller diameter, a core rotatably positioned within the bore in said mandrel and having a reduced extension rotatably positioned within the bore of the extension of said mandrel, said mandrel having a lateral slot communicating with the bore therethrough, a screw extending through said slot and secured to said core, said screw serving to prevent longitudinal movement of said core with respect to said mandrel and limiting angular movement of said core with respect to said mandrel, the extension of said mandrel having a lateral bore communicating with the bore therethrough, the extension of said core having a longitudinally cut away portion throughout its length to form a cam, a ball positioned within said lateral bore in th extension of said mandrel adjacent said cam, said core being angularly movable with respect to said mandrel to cam said ball outwardly through said lateral bore in the extension of said mandrel so that said ball projects exteriorly of the extension on said mandrel, said core extending etxeriorly of said mandrel at the end opposite said extension on said mandrel, and means associated with said core to rotate said core with respect to said mandrel within the limits defined by said screw and said slot and then to rotate both said core and said mandrel.

ALFRED CHAMPION.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,917,925 Cogsdill July 11, 1933 2,122,725 Scholtes July 5, 1938 2,183,921 Renter Dec. 19, 1939 2,377,406 Dedrick g June 5, 1945 

